The Prince of Wales has shared a heartfelt message to his wife, Kate, on her 43rd birthday, calling her the “most incredible wife and mother.” He praised her for her strength throughout a challenging year, especially after her cancer diagnosis.

The personal message was posted on their official social media profiles, with the prince signing off with a “W.”

Along with the message, a new, unseen black-and-white photo of Kate was shared, taken by Matt Porteous in Windsor last summer. In the picture, Kate, wearing a gingham scarf, smiles while casually resting her hands in her jean pockets.

William’s message read: “To the most incredible wife and mother. The strength you’ve shown over the last year has been remarkable. George, Charlotte, Louis and I are so proud of you. Happy Birthday, Catherine. We love you. W”

The royal family also posted a birthday tribute on the monarchy’s official social media, saying, “Happy Birthday to The Princess of Wales!” with a birthday cake emoji. The post was paired with a photo of Kate smiling as she received flowers from wellwishers at a church service in Sandringham on Christmas Day.